1. World Health Organization (2012) Urban Population Growth: Situation and Trends in Key Indicators. Global Health Observatory.
2. United Nations (2010) World Urbanization Prospects: 2009 Revisions. New York: United Nations Department of Economic and Social Affairs of the United Nations Secretariat.
3. Biodiversity conservation and the extinction of experience;JR Miller;Trends in Ecology & Evolution,2005
4. The extinction of experience;RM Pyle;Horticulture,1978
5. Morris N (2003) Health, well-being and open space. Edinburgh: Edinburgh College of Art and Heriot-Watt University.